WELCOME & VIDEO PRESENTATION
International Workshop on Forecasting Rainfall and lightning induced Hazards at European Scale
Heavy rainfalls are the triggering agent of a number of natural hazards affecting our society through their impacts over the outdoor exposed activities and assets. Classically floods, and specifically flash floods, have been considered the main natural hazard directly caused by heavy rainfalls, but this perception is moving towards the new paradigm of "heavy rainfall induced hazards" as new areas of relevant socioeconomic interest requiring specific hazard assessment appear.
Regarding all these weather-affected activities, and more precisely in the case of Flash Floods, the main requirement is to anticipate the occurrence of heavy rainfalls with high spatial and time resolution. Capability that is the crucial point to provide appropriate hazard assessment to be used by Civil Protection authorities.
The advancements of the last decades in rainfall forecasting with Numerical Weather Prediction models have been recently completed with the improvements on the very short-term rainfall forecasting (called nowcasting) using radar rainfall composites. The high-resolution of radar-based estimates and their capability to capture the short-term evolution of the rainfall field make them a crucial source of information to anticipate the effects of these intense rainfalls.
The EU Civil protection Prevention and Preparedness project HAREN has developed a high-resolution system for rainfall monitoring and forecasting that has been used to demonstrate its ability to support the anticipation of rainfall-induced hazards at European scale. It capitalizes on the recent improvements on nowcasting techniques, some of which developed and tested within several FP6 and FP7 EU projects, and on the European radar precipitation composites generated within the EUMETNET program OPERA and available since early 2011.
Besides of the obvious advantages of monitoring the precipitation field over Europe at high resolution, HAREN has showed that the use of OPERA radar mosaics support the generation of reasonable highresolution forecasts for lead times up to 3-6 hours. Also, advanced developments have been made to assess the uncertainty in the radarbased nowcasting by means of different approaches to provide probabilistic ensemble nowcasting.
The present HAREN Workshop is a collaborative effort with the Emergency Response Centre (DG ECHO) to show the results of the project, which essentially prove the crucial value of the OPERA European radar composites.
A number of recognized specialists have been invited to provide details about the techniques of rainfall nowcasting, its transformation into rainfallinduced hazard assessments and about the results obtained during the HAREN verification tests.
The workshop is oriented to Emergency managers from Civil Protection Centres and to the Meteorological forecasters supporting them, and it wants to promote a discussion about how to face together the challenge of facing rainfall-induced hazards at European Scale in the XXI century.
Objectives
Precipitation is one of the agents leading to natural hazards that have very serious impacts on people’s life and goods: i.e. floods, debris flows, landslides...
The challenge faced by this Project is monitoring and forecasting the precipitation field at very high-resolution to produce better assessment of hazards induced by precipitation at local scale all over Europe.
With this aim, the Project will focus on the use of the Continental precipitation maps generated from the National radar networks in Europe within the EUMETNET programme OPERA (Matthews et al. 2011). OPERA has succeeded in generating a European precipitation field in real time with the resolution of radar measurements (2x2 km2 and every 15 minutes), which fulfils the requirements of many applications involved in assessing precipitation-induced hazards used for decision-making in Civil Protection agencies.
Besides of the obvious advantages of monitoring the precipitation field over Europe at high resolution, it has been showed that the use of Continental radar mosaics allows clear improvement, providing reasonable forecasts for lead times up to 3-6 hours (as showed, e.g., by Germann et al. 2006 using the U.S. radar mosaics).
Also, recent developments have been made to assess the uncertainty in radar-based nowcasting by means of different approaches to provide probabilistic ensemble nowcasting (e.g. Berenguer et al. 2011; Koistinen et al. 2011).
The goal of the Project is thus to develop a system for precipitation monitoring and forecasting to be used in the anticipation of hazards induced by precipitation at local scale and over Europe. The Project will capitalize on the OPERA mosaics and on the recent improvements on nowcasting techniques, some of which developed and tested within several FP6 and FP7 EC projects (among others FLOODSITE, HYDRATE, and IMPRINTS (www.imprints-fp7.eu), to generate high-resolution precipitation forecasts and hazard identification over Europe, as well as the associated uncertainty of these products.